Various types of shoe presses and the like are commonly used for performing pressing operations on a running fibrous web in a paper or board machine. For instance, in the press section of a paper or board machine, the running web is dewatered by pressing the web in one or more shoe presses. Each of the shoe presses comprises a press shoe and a counter roll which between themselves form an extended nip through which the running web is carried by a circulated flexible belt. At least one loading cylinder is arranged between a supporting beam of the shoe press and the press shoe and adapted to press the press shoe against the counter roll.
There is frequently a desire to be able to vary the character of the pressure profile exerted on the running web in the nip of a shoe press, particularly in the machine direction along which the web travels. Accordingly, various mechanisms have been developed for shifting the position of a center of load exerted on a press shoe.
For example, a shoe press with a device for moving a press shoe relative to the shoe press center line containing the center line of the counter roll is known from FIG. 6 in DE-331 74 57 A1, in which the device comprises a hydraulic-fluid-actuatable tube and a spring. Various other devices for moving the center of gravity of the supporting forces acting on the press shoe relative to the press shoe are disclosed in U.S. Pat. No. 4,713,147, in which a press shoe support between the press shoe and the frame system of the shoe press is movable in the machine direction relative to the press shoe. In a variant, this press shoe support is a hydraulic-fluid-actuatable loading cylinder for pressing the press shoe against the counter roll. The press shoe support is engaged by a set screw journaled in a stationary frame of the shoe press. Rotation of the set screw causes the shoe support to be translated in the machine direction relative to the press shoe.